1. Field of the Invention
The present invention relates to a disc changer comprising a simple mechanism for preventing an occurrence of abnormal noise caused by vibration.
2. Description of the Related Art
A disc changer disclosed in Japanese Patent Application Laid-open No. 10-21630 previously filed by the Applicant comprises: a disc storage device removably inserted into an apparatus main body while holding a plurality of discs arranged in a stacked state; a disc reproduction device comprising a clamper for holding a disc from above, a turn table on which the disc is placed, and a pickup that is movable in a radial direction of the disc to read information recorded in the disc; and an elevation device for elevating the disc reproduction device in the stacking direction of the discs stored in the disc storage device.
The disc changer will be described with reference to FIG. 10 and FIG. 11.
As shown in FIG. 10, the disc changer comprises a casing 100 of the apparatus main body so that a magazine 101 serving as a disc storage device is stored in a space at the left-hand portion of the casing 100. The magazine 101 has trays 104 on which a plurality of discs 103 can be placed from an opening 110 to store them in these trays 104 and removed therefrom. The magazine 101 can be loaded into the casing 100 so that the opening 110 is directed to an X-axis direction (i.e., the transverse direction of the disc changer) and unloaded therefrom by means of a magazine eject mechanism (not shown). The loading and unloading direction relative to the casing 100 of the magazine 101 include a Z direction (i.e., the longitudinal direction of the disc changer) that extends vertically to both of the X-axis direction and the Y-axis direction (i.e., the vertical direction of the disc exchanger).
A disc reproduction device 102 comprises a stage chassis 105 on which a clamper is mounted; and a carriage chassis 106 on which a turntable and a pickup are mounted. The stage chassis 105 can be elevated together with the carriage chassis 106 in the Y-axis direction. Although a mechanism for the elevation is not shown, for example, slide members are disposed respectively on both front and rear faces in the Z direction of the casing 100. These slide members are constructed to be slidably engaged with, guide pins protruded from the stage chassis 105 and the carriage chassis 106, respectively. When the slide members moves relatively in the X-axis direction along both first and rear faces of the casing 100, the disc reproduction device 102 is elevated in the Y-axis direction. By the elevation mechanism, the disc reproduction device 102 moves to a position at which a disc 103 selected by a user is stored.
The disc reproduction device comprises a disc transfer mechanism (not shown). The disc transfer mechanism is engaged with the tray 104 for the selected disc 103 so as to draw the tray 104 to a disc reproduction position. The disc reproduction device 102 reproduces the disc 103 on the tray 104, which is drawn from the magazine 101 to the disc reproduction position.
In the thus constructed disc changer, for example, when a user presses a magazine eject button or the like (not shown) provided on the apparatus main body, the elevation mechanism moves the disc reproduction device 102 to the standby position, i.e., the storage position of the disc 103 placed on the tray 104a at the top stage of the magazine 101 shown in FIG. 10. After the disc reproduction position coincides with the disc storage position, the magazine 101 is ejected out of the casing 100 in the Z direction.
In the thus constructed disc changer, when the magazine 101 is ejected from the casing 100, the disc reproduction device 102 vibrates under the influence of external vibration, and abnormal noise may be generated. Conventionally, as a device for preventing an occurrence of such abnormal noise, an elastic member is provided on each of the casing 100 and the carriage chassis 106. The elastic member applies an elastic force to the stage chassis 105 and the carriage chassis 106, thereby attempting to prevent vibration.
A device for preventing the occurrence of an abnormal noise will be described with reference to FIG. 10 and FIG. 11.
As shown in FIG. 10, a leaf spring 107 serving as the elastic member is provided at the upper part of the casing 100 that corresponds to a position in abutment with the top face end of the stage chassis 105 when the disc reproduction device 102 moves to the standby position. When the disc reproduction device 102 is moved to the standby position by means of the elevation device, the leaf spring 107 comes into contact with the stage chassis 105, thereby applying an elastic force to the stage chassis 105 in the Y-axis direction.
In addition, as shown in FIG. 11, a leaf spring 109 serving as the elastic member is provided on the carriage chassis 106, and an engagement pin 108, which can come into contact with the leaf spring 109 is provided on the disc transfer mechanism (not shown). The engagement pin 108 serves to make a positional decision between a disc reproduction position of the disc reproduction device 102 positioned by the elevation device and the disc storage position of the disc 103 stored in the magazine 101. When the disc transfer mechanism moves in the X-axis direction in order to draw the tray 104 after the disc reproduction device 102 has been positioned by means of the elevation device, the engagement pin 108 moves in the same direction accordingly. Then, the engagement pin 108 is engaged with a guide hole 111 provided at the carriage chassis 106 to make a positional decision, and the leaf spring 109 is pressed in the same direction, whereby the carriage chassis 106 and the disc transfer mechanism turn into a united body. The disc transfer mechanism draws the tray 104 to the disc reproduction position.
More specifically, when the disc reproduction device 102 moves to the standby position described above, the leaf spring 107 shown in FIG. 10 applies an elastic force to the stage chassis 105 in the Y-axis direction. The leaf spring 109 shown in FIG. 11 applied an elastic force to the engagement pin 108 engaged with the guide hole 111 in order to make a positional decision between the disc storage position of the disc 103 placed on the tray 104 at the top stage of the magazine 101 and the disc reproduction position. By both of the above-mentioned elastic forces, the stage chassis 105 and carriage chassis 106 are stationarily held on the casing 100. In this manner, even if the disc reproduction device 102 is subjected to external vibration, the device does not generate abnormal noise. At the standby position, the disc transfer mechanism does not draw the tray 104.
However, in the conventional construction described above, the engagement pin 108 is pressed against the leaf spring 109, generating an elastic force in the X-axis direction between the former and the latter every time the disc reproduction device 102 is positioned by means of the elevation mechanism at the disc storage position of the disc stored in the magazine 101. Thus, the elastic force of the leaf spring 109 for preventing an occurrence of abnormal noise is applied to the carriage chassis 106 every time the disc is transferred. Therefore, there is a problem that a large driving force must be applied to the disc transfer mechanism in proportion to the applied elastic force. Further, the engaging pin 108 essentially serves to make a positional decision between the disc storage position of the disc stored in the magazine 101 and the disc reproduction position of the disc reproduction device 102. However, there is a problem that the engagement pin 108 urges the leaf spring 109, thereby causing displacement between the disc storage position and the disc reproduction position.
An object of the present invention is to provide a disc changer, which permits to solve the foregoing problems.
In order to solve the foregoing problems, according to the first aspect of the present invention, there is provided a disc changer comprising: a disc storage device capable of storing a plurality of discs to be arranged in a apparatus main body in a stacked state; a disc reproduction device having a carriage chassis on which first components comprising a turn table and a pickup are mounted; and an elevation device capable of elevating said disc reproduction device in a stacking direction of the disc stored in said disc storage device, wherein, a force application device is provided at a position in abutment with said carriage chassis so as to apply force to said carriage chassis, when the disc reproduction device is moved to a standby position by said elevation device, said force being applied in a direction opposite to a movement direction of said disc reproduction device toward said standby position.
According to a second aspect of the present invention, there is provided a disc changer of the first aspect, wherein said disc reproduction device has a stage chassis on which at least one second component comprising a clamper is mounted, and said disc reproduction device is stationarily held relative to said apparatus main body through transmission of said force caused by said force application device to said stage chassis, leading to application of said force to both of said carriage chassis and said stage chassis in the directions opposite to the movement direction of said disc reproduction device toward said standby position.